Pilot valve for steam traps



H. W. JUSTUS PILOT VALVE FOR STEAM TRAPS Filed OGb. 24, 19 35 nllh 51 EIIIIILIIII /&

ATTO R N EY Patented Mayo, 1931 UNlTEDSTATES PATENT OFFICE PILOT VALVETBbAPB Henry W. Justus, Napanooh, N. 1.

Application October 24, 1935, Serial No. 46.480

claims.

This invention relates to new and useful improvements in a pilot valvefor steam traps.

The invention has for an object the construction of a pilot valve whichis adapted to snap 6 into open position. This invention has particularapplication to a contrivance as illustrated in I my Patent No. 1,679,309for a Steam trap granted on July 31, 1928.

I have discovered that unless a pilot valve is 10 provided which snapsinto the open position, there is a tendency for the valve to only openpart way during the latter stages of the slow collection of condensationin the trap with a resultant undue wearing out of the trap due tounnecessary l strains and stresses. Furthermore, it is necessary thatthe pilot valve snap into open position to obtain eificient operation ofthe steam trap.

It is an object of this invention to so construct the pilot valve thatthe steam pressure 20 in the trap is utilized in snapping the valve intothe open position.

Another object of the invention is the construction of a device asmentioned which is simple and durable and which may be manufactured g5and sold at a reasonable cost.

For further comprehension of the invention, and of the objects andadvantages thereof, reference will be had to the following descriptionand accompanying drawing, and to the appended claims in which thevarious novel features of the invention are more particularly set forth.

. In the accompanying drawing forming a material part of thisdisclosure:

35 Fig. 1 is a vertical sectional view of a contrivance with a pilotvalve embodying this invention.

Fig. 2 is a fragmentary enlarged sectional view' of the pilot valve perse.

The pilot valve for steam traps, according to i this invention,comprises a valve body Ill adapted to be mounted through the wall i I ofa steam trap ii. A steam valve seat i2 is formed in a bushing i2 mountedupon the inner end of the 5 valve body iii, and communicates with aninwardly extending cylindrical wall l3 from the sides of .which thereare steam passages it which enter the interior of the steam trap H. Asteam release valve seat l5 is formed in a bushing l5 fio mounted on theouter end of the valve body Ill, and communicates with an outwardlyextending cylindrical wall Hi from which several steam passages liextend to a chamber I8 adapted to be connected by a'pipe 19 to a nearpoint of a con- 65 densation return line 20 and 20'; The return line 20and 20' is controlled by an automatic valve 2| as hereinafter furtherdescribed.

A steam valve 22 consists of a conical portion 22 engageable upon saidsteam valve seat It and a cylindrical portion 22 engaging the said 5cylindrical wall it, and in a closed position of the valve covering thesaid steam passage M, and in an open position of the valve exposing saidsteam passage It. A steam release valve 28 consists of a conical portion23 engageable upon the said steam release valve seat It, and acylindrical portion 23 engaging said cylindrical wall iii, and in aclosed position of the valve covering said release passages i7 andexposingonly a portion of the conical portion 23 to the steam from thetrap, while in a slightly opened position exposing the entire conicalportion to the trap steam.

A means is provided forconnecting the valves 22 and 23 for unitarymotion so that when one opens, the other closes. This means comprises aconnecting rod 2% attached at its ends to the valves respectively. Thisconnecting rod has a universal joint 25 interposed intermediate of itsends so that there is no interference to the prop er seating of thevalves. A pipe line 2% is con- 5 nected from the space it between thevalves 32 and 23 and extends to the top of a diaphragm control device 21which controls the valve 2i. Within the diaphragm device 21 there is thediaphragm 2'? which is connected with a valve 39 stem 28 which operatesthe valve 2i. A spring 29 normally urges the valve 2i into an openposition to allow the waterto be blown out, but the action of the steamagainst the diaphragm 21 normally holds the valve ii in a closedposition.

A float 3t is located within the steam trap it. This float 3B isconnected by a linkage system to operate the valve 22 and includes anarrangement to provide a certain amount of lost motion or play. Thus,the float 38 may be lifted or dropped through certain distances beforethe valve 22 is moved. This linkage consists of a pair of substantiallydiametrically opposite arms as and s2 fixedly mounted on a ring la whichthreadedly engages the inner end oi the body it. A lever 33 is connectedat one end to the float so and at the other end pivotally upon the armSt. A link 34 is connected intermediate the link 33 and is substantiallyparallel to the arm 32 and connects with an arm 36 which is pivotallycon nected at its other end upon the arm 32. A pin -31 projects from thearm 36 and engages in an elongated slot 38 in an extension stem 22 oithe valve 22. It is this slot which permits the iloat cient strength tohold the valve 22 open against,

the closing effect produced by the trap steam engaging the small exposedportion of the valve 28. The spring 39 is of insufilcient strength tohold the steam from the trap when acting against the entire cone portion23 from closing the valve 22.

The valve seat I! and passages ii are formed in said bushing i5 which isthreadedly mounted on said valve body iii. The valve seat i2 andpassages M are formed ingsaid bushing i2 which is threadedly mounted onsaid valve body iii.

The operation of the device is as follows:--In the condition of thedevice shown in Fig. 2, trap steam may pass from the trap H through thepassages l4 to the chamber i0" and then along the pipe 26 to the top ofthe diaphragm 21 and hold the valve 2| close so that water from the trapcannot blow out. The steam pressure from the trap against the smallexposed portion of the valve portion 2'3 is inadequate to lift the valve23 against the holding of the spring 38.

When the water level in the trap ii reaches a predetermined amount thepin 31 will strike the top of the slot 38 and slightly lift the valves22 and 23. Instantly, the steam pressure from the trap acts against theentire portion 23 and snaps the valve 23 open and the valve 22 closed.The pressure of steam abovethe diaphragm 27 now escapes through the pipe26, the passages ii, and the pipe ill to the blow off 20 and 20'.

The spring 29 then opens the valve 2| and the Water of condensation fromthe trap blows off untilthe water level in the trap has fallensufilciently for the pin 31 to strike the bottom of the slot 38. Thenthe valve 221s opened and the valve 23 closed by the downward motion ofthe float 30. The steam from the trap then passes through the pipe 26 tothe top of the diaphragm 2'! and closes the valve 2 i. Condensed waternow again collects in trap lifting the float and the device is now readyto repeat its operation.

While I have illustrated and described the preferred embodiment of myinvention, it is to be understood that I do not limit myself to theprecise construction herein disclosed and the right is reserved to allchanges and modifications coming within the scope of the invention anddefined in the appended claims.

Having thus described my invention, what I claim as new, and desire tosecure by United States Letters Patent is: I

1. In a pilot valve for steam traps, a valve body mounted through thewall of a steam trap, a valve mounted in said valve body, a float forlocation in said steam trap, and linkage interposed between said floatand said valve and having a certain amount of lost motion to control themovement of said valve, comprising fixed fulcrum bearing arms mounted onthe inner end of said valve body, a lever connected to one of said fixedfulcrum bearing arms and with said float, a. lever connected with theother of said fixed fulcrum bearing arms and having a pin engaging aslot in a stem extending from said valve, a link connecting thelatter-mentioned lever with the lever supporting said float, andresilient means normally urging said valveinto an open position.

2. In a pilot valve for steam traps, a valve body mounted through thewall of a steam trap, a valve mounted in said valve body, a float forlocation in said steam trap, and linkage interposed between said fioatand said valve and having a certain amount of 10st motion to control themovement of said valve, comprising fixed fulcrum bearing arms mounted onthe inner end of said ,valve body, a lever connected to one of saidfixed mally urging said valve into an open position,

comprising, a spring mounted upon the lever having the pin engaging theslot, and acting against the extended stem of said valve.

3. In a pilot valve for steam traps, a valve body mounted through thewall of a steam trap, a valve 1 mounted in said valve body, a stemextending from said valve into said trap and having a slot therein, afloat for location in said steam trap, fixed fulcrum bearing armsmounted on said valve body, a lever connected with one of said fixed 1fulcrum bearing arms and said float, a lever connected with the other ofsaid fixed fulcrum bearing arms, a pin on said latter-mentioned leverand engaging said slot, a linkage connecting the latter-mentioned leverwith the lever supporting said float, and a spring mounted upon thelever having the pin engaging said slot, and acting against the extendedstem of said valve to normally urge said valve into an open position.

4. In a pilot valve for steam traps, a valve body mounted through thewall of a steam trap, a valve mounted in said valve body, a stemextending from said valve into said trap and having a slot therein, afloat for location in said steam trap, fixed fulcrum bearing armsmounted on said valve body, a lever connected with one of said fixedfulcrum bearing arms and said float, a. lever connected with the otherof said fixed fulcrum bearing arms, a pin on said latter-mentioned leverand engaging said slot, a linkage connecting the latter-mentioned leverwith the lever supporting said float, and a spring mounted upon thelever having the pin engaging said slot, and acting against the extendedstem of said valve to normally urge said valve into an open position,said levers having a certain amount of lost motion and with the aid ofsaid spring control the movement of said valve.

HENRY w. .wsrus;

